Which is when they were still actively developing an AR system, before deciding against it: http://www.theverge.com/2013/5/18/4343382/technical-illusions-valve-

Which is when they were still actively developing an AR system, before deciding against it: http://www.theverge.com/2013/5/18/4343382/technical-illusions-valve-augmented-reality-glasses-jeri-ellsworth-rick-johnson http://www.theverge.com/2013/5/18/4343382/technical-illusion...